The present invention relates to a revolution type compressor which is constructed by housing a compression mechanism for compressing a refrigerant, a drive shaft for driving the compression mechanism, and an electric motor for rotating the drive shaft in a hermetically sealed chamber, and fixedly providing a balance weight for balancing a rotating mass of the aforementioned compression mechanism at the aforementioned drive shaft.
As the conventional revolution type compressor, there are known the ones each constructed by housing a compression mechanism for compressing a refrigerant, a drive shaft for driving the compression mechanism, and an electric motor for revolving the drive shaft in a hermetically sealed chamber (hermetically sealed container), as described in JP-A-2001-218411, JP-A-2001-234863 and JP-A-2000-73977, and the aforementioned electric motor includes a stator fixed to the hermetically sealed container, and a rotor connected to a drive part. Further, a balance weight for balancing the rotating mass of the aforementioned compression mechanism is disposed at the aforementioned drive shaft, and the balance weight is constructed into a cylindrical shape by a weight part in a substantially semicircular column shape for balancing the rotating mass, and a substantially semi-cylindrical cover part provided at an opposite side in the radial direction from the weight part. It is known that the cylindrical balance weight prevents agitation of the refrigerant to suppress oil churn.